Therese Plaehn has certainly been busy since her days performing in musicals at the all-girls Notre Dame Academy in Hingham. “I was really tall so I’d play, like, Rooster in Annie,” she says with a laugh. With roles on Broadway and in film under her belt, Plaehn’s starring in the national tour of Stephen Karam’s comedy-drama The Humans as whipsmart lawyer Aimee. We caught up with her before she hits the Boch Shubert Theatre stage on March 13-25.

What was your early experience in the Boston theater scene like? The first play I did there was The Well of the Saints, which is a John Millington Synge play that I did with the Súgán Theatre Company, an Irish theater company. That was a really wonderful experience with such incredible actors. And I’ve worked at the [American Repertory Theater]. I went to grad school at A.R.T. and I did Paradise Lost there and a bunch of institute shows. And then I did Our Town at the Huntington, which was David Cromer’s production that he directed and came back to play the stage manager for part of it. And that was hugely eye-opening. It was such a huge cast, and so I was able to really get to know a lot more people in the Boston theater scene and realize what a special community it is with just some of the most talented people.

Is it intimidating knowing that loved ones are in the audience watching you? Oh yes. I prefer strangers to loved ones to perform for. [Laughs.] You just put a lot of pressure on yourself. And you know that people who love you want you to do well. It’s a different game sometimes. I mean, I love it when everybody comes—don’t get me wrong. But I definitely feel the pressure.

What was it like to work on Proud Mary last year? Oh, that was fun! That was through Boston Casting. I had a scene with the two leads and they were shopping and I was a snobby saleswoman on Newbury Street.

How would you describe your character Aimee in The Humans? She’s a powerhouse. She’s a lawyer. She’s super smart and she’s the most together of the Blake family members in a lot of ways. I see her as the glue that keeps everybody tension-free as much as possible. She’s sort of the diplomat but she’s also in this interesting position where she’s the most vulnerable she’s ever been in her life and she’s at a family holiday.

Is it more fun to play someone who’s vastly different from you or someone who’s similar? I think part of being an actor is that you have to find empathy in everyone and figure out what that kernel of empathy is and go from there. So I think both are interesting, but it’s more fun to do the deep dive and try to solve a puzzle and think, “How do I hook into this person?” I think what’s interesting is when you actually really connect with the language and the rhythm of the playwright and then it’s sometimes easier to find the character. So because Stephen Karam is such a brilliant playwright and he hears dialogue so well—he’s almost like a musician in the way that he’s composed this play—he does a lot of the work. This is sort of a dream experience in tons of ways, but one of the ways is because of his language.